Patent Document 1 discloses a technique of obtaining several kinds of cut pieces having desired shapes, by manufacturing a laminated plate by laminating UD prepregs (unidirectional prepregs), in each of which fiber directions are aligned in one direction, in the manner as the fiber directions are different from each other, and by cutting the laminated plate. Further, Patent Document 1 discloses a technique of obtaining a molded article by combining the cut pieces to manufacture a preform having a three-dimensional shape after obtaining the cut pieces, and then by press-molding the preform.
However, the cut pieces disclosed in Patent Document 1 are designed so that end portions of the laminated plate of the prepreg overlap in a thickness direction of the laminated plate when manufacturing the preform. That is, a portion having a non-uniform thickness occurs in the preform that is manufactured by combining the cut pieces. For that reason, since the pressure is excessively applied to the overlapped portion at the time of press-molding, there are a lot of locations at which the reinforced fibers of the obtained molded article meander. As a result, there is a problem that strength of the molded article is greatly lowered.
Also, Patent Document 1 does not disclose a specific manufacturing method for the preform. In this case, it is expected that a preform having a three-dimensional shape is manufactured at a time by sticking each of the obtained cut pieces into a desired shape by hand. For that reason since it takes a significant time in manufacturing the preform, a problem is expected in that the working efficiency is very poor.